It takes all my effort to keep my 12-strings as close as poss to perfect tuning. Like Mooh, I let their 12-stringiness do its bit for effect.

Temeprature differences play havoc with the different gauge strings anyway. Usually I like to get to a gig and get the 12-string out its case a good 45 mins before the start. 30 mins before the start I tune it. Then, 5 minutes before the start I tune it again.

Then I pray.

Hard.